Method of dyeing live human hair



United States Patent 3,117,911 METi-IGD (3F DYHKNG LIVE HUMAN EARGregoire Kalnpissis, Paris, and Raymond litigant, Bouiogne-sur-Seine,France, assignors to LOreai, a corporation of France No Drawing. FiledJuly 13, 12 59, Ser. No. 826,454 Claims priority, application FranceApr. 23, 1959 2 Claims. (Cl. 167-83) This invention relates to dyessuitable for dyeing hair, e.-g., human hair, and other keratinousfibres, and to their production and use.

It is well known to use nitroparaphenylenedia-mine as a product in thecomposition of dyeing solutions for hair or other keratinous fibres.

It is known more especially that this dyestuti has the advantage that,on the one hand, it has a great afiinity in the cold for keratinousfibres, while on the other hand it can in some cases be readilyeliminated, which is very advantageous when it is desired to effect onlya temporary dyeing. On the other hand, this dyestuff has theconsiderable disadvantage that only orange-red shades can be obtainedtherewith.

It is an object of the present invention to provide dyes which can beused for dyeing hair in deeper shades than those yielded bynitroparaphenylenediamine, for example in colours verging uponblue-violet.

It is well known that it is desirable to be able to employ dyecompositions which are capable of dyeing hair in the deepest possiblenatural shades with the minimum number of dyestufis possessing a similarmolecular configuration, whereby selectivity on certain hairs isrninirnised.

According to a first feature of the present invention there are providedas new dyes, suitable for dyeing hair or other keratinous fibres,compounds of the general formula:

ITIHCH:

wherein R represents an amino (-NH group or carboxymethylamino (-NHCHCOOH) group.

The dyes thus defined, when applied to human hair, are capable of givingshades verging upon blue-violet when the operation is carried out at anacid, neutral or alkaline pH, e.g., a pH from 2 to 9.

It has been observed more particularly that the substitution of ahydrogen atom by a CH radical in the NH group which is situated inmeta-position in relation to the N0 group of thenitroparaphenylene-diamine produces a deepening of the shade and thusconstitutes a principal advantage of the dyes according to the presentinvention.

it has also been observed that if, in accordance with the invention, onemolecule of monochloroacetic acid is reacted with4-amino-3-nitro-l-methylaminobenzene, a dyestutf is obtained which, whenemployed at a pH between 2 and 9, can give particularly interestingshades which verge upon blue-violet.

These dyes not only give deeper shades than nitroparaphenylene-diaminebut also give aqueous solutions whose absorption spectra in the visiblerange have confirmed the deepening elfect observed on the hair.

According to a further [feature of the present invention there isprovided a process for the production of dyes of the general formula setforth above which comprises nitrating N-rnethylacetanilide by treatmentwith a rnixture of sulphui ic and nitric acids, reducing the4-nitro-N-meth- "ice ylacetanilide thus obtained to the corresponding4-amin0 compound, acetylating the said 4-amino compound, nitrating theproduct, subjecting the N-methyl-N-acetyl-N'-acetyl-meta-nitroparaphenylene-diamine thus obtained to deacetylation toproduce 4-arnino-3-nitro-1-methylaminobenzene and, if desired, treatingthis product with monochloroacetic acid to produce4-carboxymethylamino-3- nitro-l methylarninobenzene.

The foregoing processes may be schematically illustrated as follows:

C O-CHa C O-GH I I N 02 /COCH3 /OOGHa /CO-CH3 0 H C H3 0 H3 Fe-I-CHaC OO H Acetic anhydride I I I N02 NH2 NH-COC Ha II III IV COC H3 C 0-0 HaNH-CHa C H C H3 EN 0 deacetylate H2804 N0z NO:

I I I NHCOCH3 NH-CO-CHa NH2 IV V VI NHC H3 NH-- C H:

ClCHa-C O OH N O 2 N 0 2 I I NHz NI\I VI CH2-COOH,HC1

VII

The following examples illustrate the production of the new dyes andtheir use in dyeing:

EXAMPLE 1 Preparation of 4-Amin0-3-Nitr0methylaminobenzene (a) 149 g. ofN-methylacetanilide are dissolved in 750 cc. of 96% by weight sulphuricacid, the temperature being maintained at a value below 5 C., and thereis then poured dropwise into this solution a mixture consisting of 105g. of 96% by weight sulphuric acid and 105 g. of nitric acid having adensity of 1.38.

The mixture is run on to ice, and the precipitate is separated andWashed with iced water. The product is then dried in an oven. There isthus obtained product II in a yield of of theory.

(17) There are successively introduced into a three-litre round-bottomedflask provided with a stirrer and a reflux condenser 1600 cc. of water,16 cc. of glacial acetic acid and 480 g. of iron filings. Thetemperature is then raised a to 90 C. and 310 g. of the previouslyobtained product II are progressively introduced.

The product is neutralised with sodium carbonate, filtered, washed withboiling water and cooled, and there are added to the filtrate 500 g. ofacetic anhydride. The mixture is maintained at 80 C. for about 30minutes. After cooling, the product is neutralised with a caustic sodasolution to a pH which is alkaline to phenolvphthalein.

The product, which is compound IV, is filtered, Washed With water andthen dried in vacuo, the yield being 88% of theory.

92.5 g. of this product are dissolved in 410 cc. of 96% by Weightsulphuric acid, and a mixture of 372 g. of 96% by Wegiht sulphuric acidand 27.1 g. of nitric acid having a density of 1.52 is added dropwise,the temperature being maintained at about 0 C.

When the reaction has ended, the product is poured on to ice and thendiluted with water. It is thereafter heated for 1 hour at about 9095 C.,cooled and then neutralised with ammonia. There is thus obtained4-amino-3-nitro-1-methylaminobenzene (compound VI) in a yield of 85% oftheory. This substance melts at 115116 C. after recrystallisation fromwater.

EXAMPLE 11 Preparation of 4-Carb0xymethylamin0-3;Nitr0-1-Methylaminobenzene a) Into -a three-necked round-bottomed flask providedwith a thermometer, a dropping funnel, a reflux condenser and amechanical stirrer are introduced 0.1 mole.

of 4-amino-3-nitro-1-methylaminobenzene, 0.14 mole of precipitatedcalcium carbonate and 150 cc. of Water.

The mixture is brought to boiling point and an aqueous solution of 0.125mole of monochloroacetic acid isthen added dropwise.

EXAMPLE III A :lock of white hair is dipped into cc. of a solutionconsisting of:

4-amino-3-nitro-l-methylaminobenzene g 0.1 ammonia, q.s. for pH 8.Water, q.s. for 10 cc.

The lock of hair is left in contact with the solution for 20 minutes at20 C. It is then shampooed, rinsed with water and dried with Warm air.It is tinted an intense reddish violet.

EXAMPLE IV A lock of white hair is dipped into 10 cc. of a solutionconsisting of:

4-amino-3-nitro-l methylaminobenzene, hydrochloride lg. 0.1

Water, q.s. for 10 cc.

The solution thus obtained has a pH of about 7.2.

The lock of hair is left in contact with the solution for 20 minutes atabout 20 C. It is then shampooed, rinsed with water and dried with warmair (about -40 C.).

A beautiful reddish-violet shade is obtained.

When the evolution of carbon dioxide has stopped, the reaction mixtureis acidified by the addi- EXAMILE v A lock of white hair is dipped into10 cc. of a solution consisting of:

4-amino-3-nitro-l-methylaminobenzene g 0.1

Lactic acid, q.s. for pH 6. Water, q.s. for 10 cc.

The lock of hair is left in contact with the solution for 20 minutes atabout 20 C. It is then shampooed, rinsed with Water and dried in theair.

The shade obtained is reddish violet.

EXAMPLE VI A lock of white hair is dipped into 10 cc. of a solutionconsisting of:

4-carboxymethylamino-3-nitro-l-methylaminobenzene, hydrochloride g 0.520% ammonia, q.s. for pH 8. Water, q.s. for 10 cc.

The lock of hair is left in contact with the solution for 20 minutes atabout 20 C. It is then shampooed, rinsed with Water and dried in theair.

The shade obtained is pink-beige.

EXAMPLE VII A lock of white hair is dipped into 10 cc. of a solutionconsisting of:

4-carboxymethylamino-3-nitro-1-methylaminobenzene, hydrochloride g 0.5Water, q.s. for 10 cc. The solution thus obtained has a pH of about 2.

The lock of hair is left in contact 'with the solution for 20 minutes atabout 20 C. It is then shampooed, rinsed with water and dried in theair.

The shade obtained is blue-violet.

EXAMPLE VIII A lock of hair is dipped into a solution having an acid pHand consisting of:

4-carboxymethylamino-3-nitro-1 methyl-aminobenzene, hydrochloride g 0.12Crystallised sodium acetate g 0.12 Water, q.s. for 10 cc.

References Cited in the file of this patent UNITED STATES PATENTS2,580,284 Deahl et al Dec. 25, 1951 2,750,326 Eckardt June 12, 19562,750,327 Eckardt June 12, 1956 2,814,646 Kolka et a1 Nov. 26, 19572,889,315 Bossard et al. June 2, 1959 2,943,109 Ramsey June 28, 1960OTHER REFERENCES Venkataraman: The Chemistry of Synthetic Dyes, vol.

1, 1952, page 323.

Heilingoiter, The Amer. Perfumer and Essential Oil Review, May 1954, pp.345-348, particularly page 347.

1. A METHOD OF DYEING LIVE HUMAN HAIR, WHICH CONSISTS ESSENTIALLY OFDYEING SAID HAIR WITH AN AQUEOUS SOLUTION OF THE COMPOSITION4-CARBOXYMETHYLAMINO-3-NITRO-1-METHYLAMINOBENZENE.
 2. A METHOD OF DYEINGLIVE HUMAN HAIR, WHICH CONSISTS ESSENTIALLY OF DYEING SAID HAIR WITH ANAQEUOUS SOLUTION OF THE COMPOSITION4-AMINO-3-NITRO-1-METHYLAMINOBENZENE.